Devices for introducing multiple instruments and methods of use

ABSTRACT

Disclosed herein are devices and methods for introducing a plurality of instruments to a target site through a working channel. The working channel can include a surface adapted to guide one or more instruments into select positions. The working channel can be defined by a portion of a guide tube or tip that may be coupled with an endoscope.

This application claims the benefit of priority from U.S. ProvisionalApplication No. 61/249,317, filed Oct. 7, 2009, which is hereinincorporated by reference in its entirety.

FIELD OF THE INVENTION

Embodiments of the present invention relate to devices used forendoscopic surgery. In particular, exemplary embodiments of the presentinvention relate to devices for introducing multiple instruments to asurgical site. Embodiments of the present invention also cover methodsof using such devices.

BACKGROUND OF THE INVENTION

Endoscopic surgery usually involves accessing a surgical site through asmall incision in the patient's body or a natural body orifice. One goalof endoscopic surgery is to reduce tissue trauma and the body's responseto injuries associated with traditional “open” surgery. Examples of somecommon endoscopic procedures include laparoscopic cholecystectomies(i.e., gall bladder removal) and appendectomies; arthroscopic surgery ofthe interior of bone joints; endoscopic rhinosinusitis; colonoscopicexcisions; endoscopic discectomy; etc. In addition to medicalapplications, endoscopic systems may be used for visualization andmanipulation of complex technical systems, improvised explosive devices,architectural scale models, and other non-medical applications.

Conventional endoscopes are often configured to deliver optical devicesand surgical instruments to a surgical site. Such optical devicesusually include two fiber optic lines for imaging the site. A “lightfiber” carries light to the site, while an “image fiber” carries animage of the site back to the endoscope's operator.

Conventional endoscopes typically include a working channel forintroducing surgical instruments to a target surgical site. Theseinstruments can have end-effectors, such as forceps, scissors, brushes,etc. for tissue excision, sampling, or other diagnostic and surgicalwork. Some endoscopes can also include a separate axial port or channelfor administration of drugs, suction, or irrigation.

The growing capabilities of endoscopes have allowed operators to performan increasing variety of surgeries and diagnostic and/or therapeuticprocedures. Further refinement of endoscopic devices may enableoperators to less invasively perform complicated procedures, therebyreducing post-operative pain, scar tissue formation, or recovery time.Reducing the size of endoscopic equipment also would allow greateraccess to target sites within body regions that are currently difficultto treat with conventional endoscopic systems.

Conventionally multiple instruments for endoscopic procedures aredelivered to the target site through separate working channels of asingle endoscope. These separate working channels running the fulllength of the endoscope maintain the positions of the instrumentsrelative to one another, relative to optics, and relative to the body ofthe endoscope. For example, a grasper inserted through a left-sidechannel of a conventional endoscope will be located to the left of agrasper inserted through a separate right-side channel throughout thelength of the endoscope.

Conventional endoscopes having two or more working channels can be largeand unsuitable for some endoscopic procedures. The elimination ofseparate working channels within at least part of an endoscope couldreduce the diameter of at least part of the endoscope. Additionally, theability to deliver multiple instruments through a single lumen increasesthe number of instruments available at the surgical site. Deliveringmultiple instruments simultaneously may facilitate more complexendoscopic surgeries.

The present disclosure describes devices and methods for deliveringmultiple instruments to a surgical site.

SUMMARY OF THE INVENTION

Described herein are various devices for introducing a plurality ofinstruments to a target site through a single channel of an elongatebody. For example, embodiments of the current disclosure provide adevice having a single proximal lumen that can divide into multipledistal lumens. Such a design can lower a radial dimension of the deviceby removing the need for individual channels to carry individualinstruments.

In one aspect, the system may comprise an elongate guide tube ordistally mounted working channel tip having at least one working channelthrough which multiple instruments may be delivered to the target site.The tip or guide tube can include a lumen configured to direct a firstinstrument into a first select position, and then permit a secondinstrument to be directed to a second select position. Thus, a portionof the tip or guide tube can provide an instrument directing surfacesuch that an instrument delivered through the tip or guide tube can bepositioned in a location relative to the body of the tip or guide tube,or relative to another instrument delivered through the tip or guidetube.

In one aspect, the working channel of a tip or guide tube can beconfigured to receive two instruments. The instrument directing surfacecan operate to directionally bias a first instrument, such as, forexample, deflecting the first instrument toward a right hand side of thetip or guide tube. The first instrument or the instrument directingsurface then affects the movement of a second instrument deliveredthrough the working channel to assume a left-handed position.

The instrument directing surface can be positioned on or in a workingchannel of the tip or the guide tube. In one aspect, the tip can beintegrally formed with the guide tube. In another aspect, the tip can bedetachably coupled to the guide tube. The detachable tip can bedisposable or can mate with an off-the-shelf endoscope to allow the useof multiple tools in a single conventional endoscope working channel.

Further described herein are methods of introducing a plurality ofendoscopic instruments to a target site. In one embodiment, a guide tubehaving at least one working channel and a distal working channel tip maybe directed to a target site. At least two surgical instruments then maybe delivered through the working channel and the distal tip, wherein theshape and size of an inner surface of the tip directs the instrumentsinto select positions within the tip.

In yet another aspect, the tip or guide tube includes multiple distalworking channels that branch from a single proximal working channel. Oneor more instrument directing surfaces can direct multiple instruments,inserted into the proximal working channel sequentially, into selectdistal working channel branches. For example, an endoscope may bedirected to a centrally-located distal working branch. Two subsequentlyinserted instruments may then be directed to generally left-side andright-side, or off-center, distal working channel branches.

The applications of the disclosed systems and methods include, but arenot limited to, trans-oral, trans-anal, trans-vaginal, trans-nasal,laparoscopic, arthroscopic, thoracoscopic, and panendoscopic surgeries.In addition, while the described systems and methods may generally referto “surgical instruments” for convenience, they are not limited tosurgical, or other therapeutic, interventions. In particular, thedescribed systems and methods may be used for various diagnosticapplications, such as collection of tissue biopsy samples, gastroscopyfor visualization of ulcers within the upper GI tract, hysteroscopy fordiagnosis of intrauterine pathology, etc. In addition, the systems andmethods described herein can be used for non-medical applications, suchas the inspection or repair of machinery.

It is to be understood that both the foregoing general description andthe following detailed description are exemplary and are not restrictiveof the invention, as claimed.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in and constitute apart of this specification, illustrate embodiments of the invention andtogether with the description, serve to explain the principles of thedisclosed system, devices and methods.

FIG. 1 is a perspective view of an exemplary embodiment of a systemdescribed herein.

FIG. 2A is a cross-sectional view of FIG. 1 taken along line A-A′.

FIG. 2B is a cross-sectional view of another embodiment of a system.

FIG. 3 is a cross-sectional view of another embodiment of a system.

FIG. 4 is a cross-sectional view of another embodiment of a system.

FIG. 5A is a longitudinal sectional view of the distal end of anexemplary embodiment.

FIG. 5B is a longitudinal sectional view of the distal end of anexemplary embodiment showing a first instrument.

FIG. 5C is a longitudinal sectional view of the distal end of anexemplary embodiment showing a second instrument being inserted.

FIG. 5D is a longitudinal sectional view of the distal end of anexemplary embodiment showing a second instrument being positioned inbetween a first instrument and an instrument directing surface.

FIG. 6A is a cross-sectional view of another embodiment of a system.

FIG. 6B is a longitudinal sectional view of the embodiment illustratedin FIG. 6A.

FIG. 7A is a perspective view of an exemplary embodiment showing a firstinstrument being guided into its select position by an instrumentdirecting surface.

FIG. 7B is perspective view of the embodiment illustrated in FIG. 7A,showing a first instrument and a second instrument being directed intotheir select positions.

FIG. 8A is a cross-sectional view of the distal end of an exemplaryembodiment.

FIG. 8B is a cross-sectional view of the distal end of another exemplaryembodiment.

FIG. 9A is a perspective view of an exemplary embodiment wherein theworking channel bifurcates into two branches.

FIG. 9B is a perspective view of another exemplary embodiment whereinthe working channel bifurcates into two branches showing the relativepositioning of a first instrument and a second instrument.

FIG. 9C is a perspective view of another exemplary embodiment whereinthe working channel bifurcates into three branches showing the relativepositioning of an endoscope, a first instrument, and a secondinstrument.

DESCRIPTION OF THE EMBODIMENTS

Reference will now be made to exemplary embodiments of the invention,examples of which are illustrated in the accompanying drawings. Whereverpossible, the same reference numbers will be used throughout thedrawings to refer to the same or like parts.

FIG. 1 illustrates a perspective view of a system 10 for performing asurgical, therapeutic, or diagnostic procedure. System 10 can include aguide tube 11 and a tip 12 for delivering one or more instruments to atarget site. For example, as shown in FIG. 1, a first instrument 16 anda second instrument 17 are shown within system 10.

Instruments 16 and 17 can each include a proximally-located handle (notillustrated) for controlling distal articulation or operation ofend-effectors 16 a and 17 a. The handles and the end-effectors 16 a, 17a can be connected by rigid or flexible catheters 16 b and 17 b,respectively. The instruments can be disposed within system 10 such thatend-effectors 16 a and 17 a can pass through system 10 and extend beyonda distal end of system 10 to a target site (not shown).

During a procedure, system 10 can be inserted into a patient through anopening and positioned near the target site. Instruments 16 and 17 canthen be inserted into system 10 through one or more lumens or channels.As discussed below, system 10 can include one or more channels for thepassage of instruments, optics, therapeutic substances, implants, orother therapeutic or diagnostic devices.

System 10 can be configured for insertion through a small incision ornatural body lumen such as the colonic lumen or other gastrointestinallumen. In one embodiment, system 10 is flexible and non-articulating. Inanother embodiment, at least a portion of system 10 includes anarticulation section. For example, a segment 13 can provide one, two, ormore than two degrees of freedom of movement to system 10. Articulationcan be controlled via proximal user controls, as described in U.S.patent application Ser. No. 11/946,812, which is incorporated herein byreference. In addition, while system 10 is described as flexible, all ora portion of system 10 can be rigid.

Guide tube 11 can include a generally elongate body 24 extending betweena proximal end (not illustrated) and a distal end 26. Guide tube 11 canalso include one or more lumens or channels extending from a generallyproximal region of guide tube 11 to a generally distal region of guidetube 11.

As shown in FIG. 2A (taken along line A-A′ in FIG. 1), guide tube 11 cancomprise a single channel configured to receive one or more instruments.For example, the outer walls of guide tube 11 can define a workingchannel 14 configured to receive instruments 16, 17.

In another embodiment, as illustrated in FIG. 2B, guide tube 11 caninclude multiple channels. For example, an optical channel 18 can beconfigured to receive an optical device 20, and a working channel 15 canbe adapted to receive instruments 16, 17. As shown in FIG. 2B, workingchannel 15 can have a generally circular cross-section, however othersuitable cross-sectional shapes may be used.

In another embodiment, optical device 20 can be integrated within thestructure of guide tube 11. Such an embodiment, as depicted in FIG. 3,can include an optical device 20 a, a light source 20 b, and a lenswasher 20 c. Various other embodiments of guide tube 11 havingarrangements of components are known to one of skill in the art.

In another exemplary embodiment illustrated in FIG. 4, working channel15 can have a generally “dumbbell” shaped cross-section to facilitatethe alignment and positioning of instruments 16, 17. The cross-sectionof the working channel lumen need not be limited to circular or dumbbellshapes, but can include any shape or configuration that would facilitatethe insertion and alignment of instruments within a channel.

As shown in FIG. 1, system 10 can include tip 12 located generallydistally along system 10. Tip 12 can function to direct the movement ofone or more instruments into one or more select, desired positions asthe instruments exit the distal end of system 10. In effect, tip 12 canoperate to generally organize the relative locations of a plurality ofinstruments.

In an exemplary embodiment, tip 12 can be defined by a portion of guidetube 11, e.g. tip 12 can be integrally formed with tube 11. In anotherembodiment, working channel tip 12 can be permanently or detachablymated to a distal region of guide tube 11. As shown in FIG. 1, tip 12can include a generally tubular structure and can be mated to distal end26 of guide tube 11. These and other embodiments permit tip 12 topreferentially orient instruments as they exit system 10. For example, atip 12 may be selected from a set of tips having different structuresthat result in different orientations/positions of the instrumentsrelative to each other.

Tip 12 can be formed of any suitable material. Such materials caninclude a metal, polymer, or biocompatible material. Tip 12 can also beformed of a transparent or translucent material to permit visualizationthrough tip 12.

Tip 12 can be adhered or mechanically coupled to guide tube 11. In onesuch embodiment, guide tube 11 and tip 12 can have complementary threadsfor connecting to each other. In yet another embodiment, tip 12 can beconfigured to mate via a snap fit. Other forms of attachment can includeadhesives or mechanical connectors. Adhesives can include UV cure epoxy,heat cure epoxy, cyanoacrylates, or tape. Mechanical connectors caninclude crimping, swaging, ultrasonic welding, metal welding orsoldering, or a bayonet mount.

In one embodiment, tip 12 can mate with a conventional endoscope or anoff-the-shelf guide tube. For example, the proximal end of tip 12 caninclude a mating feature for detachably mating with the distal end of aconventional endoscope. In one such embodiment, a portion of tip 12 canbe cinched or strapped around a portion of the endoscope.

Various devices, systems and methods may be used to removably connect ordisconnect tip 12 to guide tube 11, an endoscope, or a similar device.For example, a sleeve (not shown) can extend over a portion of guidetube 11 and tip 12 to mate the two devices. In addition, tip 12 may beattached to a full length sleeve (not shown) that an endoscope or toolis inserted into.

As shown in FIG. 5A, tip 12 can include a proximal end 27 and a distalend 29. Tip 12 can also include one or more channels or integrateddevices, such as, for example, an integrated optics device. For example,an optical channel in tip 12 can be aligned with an optical channel inguide tube 11 to permit ready passage of an optical device through guidetube 11 and tip 12.

Tip 12 can include one or more working channels which correspond to oneor more working channels of guide tube body 24. In one aspect, tip 12can include a single working channel 31. In another aspect, the workingchannel can branch from a proximally-located single working channel totwo or more distally-located openings. In yet another aspect, tip 12 caninclude multiple working channels.

In one embodiment, tip 12 can include an inner surface 22, which candirect one or more instruments into one or more select, desiredpositions. As such, surface 22 may selectively position a plurality ofinstruments. In one aspect, surface 22 directs a first instrument into afirst select position. Subsequent placement of a second instrument intotip 12 can result in the second instrument being directed to a secondselect position. The first and second positions can correspond to firstand second areas within a single working channel. Alternatively, thefirst and second positions can refer to separate working channelbranches or separate apertures.

In one aspect, inner surface 22 can include a funnel-like shapeproximate to distal end 29 of tip 12. Other generally arcuate or linearshaped surfaces may similarly be configured to direct one or moreinstruments.

FIG. 5A illustrates a longitudinal cross-section of the distal end oftip 12 with surface 22 defined by a portion of channel 31 that tapers orreduces in diameter in a proximal to distal direction. In one aspect, afirst right-hand side wall 28 has a funnel-like shape while an opposing(second) or a left sidewall 30 has a linear shape. As a firstinstrument, such as instrument 16, is inserted through channel 31, thetapered channel directs instrument 16 towards left sidewall 30.

FIG. 5B illustrates instrument 16 inserted through channel 31 and spacedaway from right sidewall 28. The shape of surface 22 can positioninstrument 16 closer to left sidewall 30 than to right sidewall 28.

FIG. 5C illustrates second instrument 17 approaching surface 22.

As second instrument 17 is inserted through channel 31, the position offirst instrument 16 relative to sidewalls 28, 30 and the shape ofsurface 22 can bias second instrument 17 toward a right position withrespect to first instrument 16. While funnel shaped surface 22 caninitially direct instrument 16 closer to sidewall 30, subsequentlyinserting second instrument 17 into working channel 31 forces secondinstrument 17 into the space between instrument 16 and sidewall 28. Assuch, surface 22 operates to generally direct instruments 16, 17 totheir respective locations relative to each other.

As instrument 17 is advanced toward distal opening 32, instrument 17comes to generally occupy the right side of channel 31. Instrument 17then passes between instrument 16 and sidewall 28. As illustrated inFIG. 5D, first and second instruments 16, 17 can extend beyond distalopening 32 to become located in positions relative to one another andrelative to tip 12.

System 10 may not be restricted to directing the relative positioning oftwo instruments as surface 22 can be configured to facilitate therelative placement of more than two instruments. For example, a thirdinstrument could subsequently be passed between second instrument 17 andsidewall 28. In another example described below with regard to FIG. 9C,an endoscope could be placed within system 10 and directed to a firstposition. Thereafter, first and second instruments may be inserted intosystem 10 and directed to two other positions, such as generally leftand right, top and bottom, or other locations relative to the endoscope.In such an embodiment, one or more surfaces 22 could direct thesequential insertion of devices to select, relative locations. Inanother example, a first inserted device could be directed to a firstposition (such as a left or top position), a second inserted devicecould be directed to a second position (such as a center position), anda third inserted device could be directed to a third position (such as aright or bottom position).

In another embodiment, surface 22 can include a first area 22 a and asecond area 22 b separated by a traversable barrier 34. As shown in theFIG. 6A, first or second areas 22 a, 22 b may have cross-sectionalwidths w and barrier 34 can have a cross-sectional width w′, where w′can be generally smaller than the cross-sectional diameter of firstinstrument 16 positioned within area 22 a of tip 12. Second instrument17 can have a diameter approximately equal to or slightly smaller thanthe diameter of first instrument 16. As shown in FIG. 6B, barrier 34 canextend across a portion of channel 31 to selectively position a firstinstrument (not shown) into first area 22 a. The first instrument thatenters channel 31 encounters barrier 34 and barrier 34 directs thisinstrument to area 22 a. The first instrument, as a result, occupies aselect position within tip 12.

Placement of a first instrument in first area 22 a can also preventpassage of a second instrument (not shown) through first area 22 a. Thesecond instrument can be forced to cross barrier 34 and occupy area 22b. Crossing barrier 34 can require some minimal amount of force suchthat as first instrument encounters barrier 34, the first instrument cantake a path of least resistance generally around barrier 34. Howeveronce in first area 22 a, the first instrument can at least partiallyblock the path around barrier 34. If an operator subsequently inserts asecond instrument into channel 31, the second instrument can be placedinto area 22 b after overcoming barrier 34. As such, barrier 34 canoperate to selectively position a first instrument into first area 22 aand selectively position a second instrument into second area 22 b.

In some embodiments, barrier 34 can be formed from part of tip 12. Asshown in FIG. 6A, barrier 34 can include a thin section of tip 12residing generally between two areas within tip 12. Barrier 34 caninclude a polymer or metal material that may be different or similar toa material used to form tip 12. Further, barrier 34 can be at leastpartially formed from a flexible or a non-flexible material.

In one aspect, barrier 34 can be formed of a compressible, deformable,bendable, elastic, or resilient material. For example, upon contact withthe second instrument, barrier 34 can change shape to allow passage ofthe second instrument into area 22 b. Barrier 34 may also include aductile or brittle material configured to rupture when a sufficientforce is applied.

In another aspect, barrier 34 can be formed of a rigid or semi-rigidmaterial. A rigid barrier 34 could include one or more spring elementsconfigured to deflect when a force is applied. These spring elementscould be surfaces which deflect when instruments are passed. Further,other spring mechanisms such as leaf or coil springs could deflect oneor more instruments or be deflected by one or more instruments.

In yet another embodiment of the systems and methods described herein,barrier 34 can be a partially ramped or protruding surface feature thatmay partially block a section of channel 31. As shown in FIG. 7A,barrier 34 can generally prevent first instrument 16 from enteringsecond area 22 b. In addition, barrier 34 can direct the firstinstrument into first area 22 a.

As shown in FIG. 7B, the ramp structure of barrier 34 can be formed of acompressible or deformable material such that second instrument 17 cancompress the ramp and occupy the position in between the ramp andinstrument 16. Instruments 16 and 17 can be positioned in theirselective area 22 a, 22 b, respectively. Also, an instrument can beformed of a compressible outer sheath, such that the body of theinstrument is compressed to permit passage through second area 22 b.

In one aspect, surface 22 can limit movement of one or more instrumentsonce inserted through system 10. For example, surface 22 can narrow to adimension corresponding to the cross-sectional size and shape ofinstruments 16 and 17. The limited spacing between the instruments andthe walls of channel 31 can inhibit relative movement of theinstruments.

FIG. 8A illustrates distal end 29 of tip 12, wherein instrument 16occupies one side of opening 32. The remaining area of opening 32 has asize and shape generally corresponding to instrument 17 (not shown).Once instruments 16 and 17 are positioned within opening 32, the sizeand shape of opening 32 can prevent lateral movement of one or moreinstruments within opening 32.

In addition, or alternatively, the distal portion of channel 31 oropening 32 can include a dumbbell cross section or a divider that limitsmovement of an instrument. For example, FIG. 8B illustrates a dumbbellshaped opening 32 having a first area located beside a second area(e.g., left and right areas) configured to receive the first and secondinstruments. After first instrument 16 is positioned within a first,right area, the instrument can be limited from moving laterally into thesecond, left area.

In one aspect, surface 22 can assist with directing instruments intodifferent branches of one or more working channels. In an exemplaryembodiment, tip 12 bifurcates into multiple branches. As illustrated inFIG. 9A, tip 12 divides into branches 12 a and 12 b. Surface 22 can bepositioned within tip 12 to selectively direct the one or moreinstruments inserted into tip 12 into branches 12 a, 12 b.

In another embodiment, a single working channel can split into multiplechannel branches. As illustrated in FIG. 9B, working channels 35 a and35 b extend from a channel 35 within tip 12. As instruments 16, 17 areinserted into working channel 35, surface 22 may direct instruments 16,17 into separate channel branches. As shown in FIG. 9B, instrument 16can be selectively positioned in branch 35 a and instrument 17 can beselectively positioned in branch 35 b.

In some embodiments, multiple instruments may exit system 10 atdiverging, converging, or substantially parallel angles. For example, asshown in FIG. 9C, instruments 16, 17 diverge from a longitudinal axis 37of tip 12 and a device 33 extends generally parallel or alonglongitudinal axis 37. Multiple channels may differently diverge,converge, or remain parallel to axis 37. Such divergence of instrumentsmay improve the triangulation of these instruments when used in surgicalprocedures.

In other embodiments, instruments 16, 17 may extend from openings alongthe side of tip 12, not located at the distal end of tip 12. Also,device 33 may include an endoscope, optical device or a thirdinstrument. It is also contemplated that instruments 16, 17 and device33 may be located in different branches or differently positioned beyondthe distal end of tip 12.

In another embodiment, surface 22 or barrier 34 can be positioned withinguide tube 11. For example, a lumen extending through guide tube 11 caninclude the various shapes and features described above with respect totip 12. Thus, guide tube 11 can be configured with one or more surfaces22, barriers 34, or lumens as described above for tip 12 to selectivelyposition a plurality of instruments passed through guide tube 11. Assuch, an operator can insert two or more instruments through a workinglumen of guide tube 11 and surface 22 within guide tube 11 can directthe one or more instruments to select locations within guide tube 11.

In yet another embodiment, system 10 can include an obturator forpreventing inflow of surgical debris or biological materials through adistal opening during insertion of system 10. Exemplary obturators aredisclosed in U.S. patent application Ser. No. 11/946,812, which isincorporated herein by reference. In one aspect, a dummy instrument canact as an obturator. If all of the channels are not occupied by surgicalinstruments, the unused channels can be blocked by dummy instruments.

An endoscopic procedure may require multiple devices to locateinstruments at a surgical site. For example, depending on the size orshape of the instruments, the number of instruments, or type ofprocedure, a user could select an appropriate tip or guide tube from anassortment of tips and guide tubes. In one aspect, multiple guide tubesand/or tips could be packaged as a single kit and delivered to anoperator. Various components may be pre-sterilized and asepticallypackaged.

Embodiments of the invention also include methods of using the systemsand devices described herein. In one embodiment, guide tube 11 havingworking channel 15 is introduced to the target site through a naturalbody orifice or a surgical incision. A first instrument, such asinstrument 16, is then inserted into guide tube 11. Instrument 16traverses through working channel 15 and enters tip 12, which includesinner surface 22 for directing instruments into selective positions. Theshape and position of surface 22 directs instrument 16 into a firstselect position within tip 12 and distally of tip 12. A secondinstrument, such as instrument 17, is then inserted into channel tip 12via working channel 15. The position of first instrument 16 relative tothe sidewalls of tip 12 and the shape of surface 22 directs instrument17 to the second select position within tip 12 and distally of tip 12.Thus, the first and second instruments 16, 17 are selectively positionedrelative to one another and relative to tip 12 and guide tube 11. In anadditional aspect, the placement of instrument 16 into the firstposition can limit instrument 17 from migrating into the first position.

In another embodiment, the first and second positions can correspond tofirst and second instrument areas 22 a and 22 b within inner surface 22of working channel tip 12 or guide tube 11. Surface 22 can furtherinclude a traversable barrier 34 which limits movement of a firstinstrument inserted into tip 12 or guide tube 11, and can direct it awayfrom second area 22 b. As a first instrument, such as instrument 16, isinserted into a working channel, it encounters barrier 34 and isdirected into area 22 a. Thus, the first instrument takes a path ofleast resistance around barrier 34, and occupies a select positionwithin the working channel and distal to the tip 12. As a secondinstrument, such as instrument 17, is subsequently inserted into channeltip 12, it encounters barrier 34 which limits its access to area 22 b.When an operator moves instrument 17 into the working channel, barrier34 can be modified, permitting instrument 17 to enter area 22 b. Thus,the second instrument can be directed to a select position relative tothe first instrument and relative to system 10.

In yet another embodiment, barrier 34 can change position, shape, orsize to permit passage of the second instrument. In an initialconfiguration, barrier 34 limits one or more instruments from enteringarea 22 b. A first instrument 16 inserted into the working channeloccupies the position 22 a because barrier 34 limits access of the firstinstrument into position 22 b. When a second instrument 17 is insertedinto the working channel, position 22 a is occupied by the firstinstrument. The second instrument encounters barrier 34 which limits itsaccess into area 22 b. When an operator applies some additional force tobarrier 34 by means of instrument 17, barrier 34 can change itsposition, shape, or size to allow passage of instrument 17 into area 22b. In one such aspect, barrier 34 is compressed or deformed by thesecond instrument. In another exemplary aspect, barrier 34 is pushed orslid into a new position that allows access to position 22 b. Barrier 34may also be hingedly or flexibly attached to tip 12 or guide tube 11.Thus, the first and second instruments 16, 17 are directed to selectpositions relative to one another and relative to the guide tube.

During a surgical procedure, the instruments can reside within system 10until they are moved into the target site for various surgical ordiagnostic applications. The instruments residing within system 10 maybe introduced into the target site either simultaneously orconsecutively, depending on the procedural requirements. Directing theinstruments into selective positions within the working channel ensuresthat instruments are released at the target site in select locationsrelative to other instruments, optics, the guide tube, or anatomicalstructure.

Other embodiments of the invention will be apparent to those skilled inthe art from consideration of the specification and practice of theinvention disclosed herein. It is intended that the specification andexamples be considered as exemplary only, with a true scope and spiritof the invention being indicated by the following claims.

1.-37. (canceled)
 38. A distal tip of a medical instrument, comprising:a body having a proximal end, a distal end, and a channel extendingalong a longitudinal axis therebetween, wherein the channel is at leastpartially defined by an instrument directing surface that is transverseto a longitudinal axis of the body, proximate to a distal end of thebody, and proximal of the distal end of the body; wherein the body isconfigured such that, when a first instrument is inserted into thechannel, the instrument directing surface contacts the first instrumentand guides the first instrument into a first area, and wherein, if asecond instrument is inserted into the channel while the firstinstrument is present in the first area, the second instrument is guidedto a second area.
 39. The distal tip of claim 38, wherein the first areais dimensioned so that it cannot receive both the first instrument andthe second instrument.
 40. The distal tip of claim 38, wherein thepresence of the first instrument in the first area limits the secondinstrument from moving into the first area.
 41. The distal tip of claim38, wherein the instrument directing surface is deformable, such that,when the second instrument is inserted into the channel, contact betweenthe second instrument and the instrument directing surface causes theinstrument directing surface to change shape and allow passage of thesecond instrument into the second area.
 42. The distal tip of claim 38,wherein the instrument directing surface forms a junction such that,proximal of the instrument directing surface, the channel is a singlechannel, and distal of the instrument directing surface, the channel hasa first branch and a second branch.
 43. The distal tip of claim 42,wherein the first area is in the first branch, and the second area is inthe second branch.
 44. The distal tip of claim 38, wherein theinstrument directing surface has at least one of a ramp shape, a funnelshape, or a tapered shape.
 45. The distal tip of claim 38, wherein thebody is removably attachable to a distal end of a guide tube of anendoscope.
 46. The distal tip of claim 38, wherein the instrumentdirecting surface is configured to obstruct the first instrument fromentering the second area.
 47. The distal tip of claim 38, wherein thefirst area and the second area are parallel.
 48. A distal tip of amedical instrument, comprising: a body having a proximal end, a distalend, and a channel extending along a longitudinal axis therebetween,wherein the channel is at least partially defined by an instrumentdirecting surface that is transverse to a longitudinal axis of the bodyand proximal of the distal end of the body, and wherein a portion of thechannel distal to the instrument directing surface includes a first areafor receiving a first instrument and a second area for receiving asecond instrument; wherein, when the first instrument is inserted intothe channel, the instrument directing surface contacts the firstinstrument and guides the first instrument into the first area, andwherein the instrument directing surface limits the first instrumentfrom entering the second area.
 49. The distal tip of claim 48, wherein,if the second instrument is inserted into the channel while the firstinstrument is disposed in the first area, the second instrument isguided into the second area by at least one of the first instrument orthe instrument directing surface.
 50. The distal tip of claim 49,wherein the instrument directing surface is deformable, such that, whenthe second instrument is inserted into the channel, contact between thesecond instrument and the instrument directing surface causes theinstrument directing surface to change shape and allow passage of thesecond instrument into the second area.
 51. The distal tip of claim 48,wherein the instrument directing surface forms a junction such that,proximal of the instrument directing surface, the channel is a singlechannel, and distal of the instrument directing surface, the channel hasa first branch and a second branch.
 52. The distal tip of claim 51,wherein the first area is in the first branch and the second area is inthe second branch.
 53. The distal tip of claim 48, wherein theinstrument directing surface has at least one of a ramp shape, a funnelshape, or a tapered shape.
 54. The distal tip of claim 48, wherein theinstrument directing surface is configured to obstruct the firstinstrument from entering the second area.
 55. A distal tip of a medicalinstrument, comprising: a body having a proximal end, a distal end, anda channel extending along a longitudinal axis therebetween, wherein thechannel is at least partially defined by an instrument directing surfacethat is transverse to a longitudinal axis of the body and proximal ofthe distal end of the body, and wherein a portion of the channel distalto the instrument directing surface includes a first area for receivinga first instrument and a second area for receiving a second instrument;wherein, when the first instrument is inserted into the channel, theinstrument directing surface is configured to obstruct the firstinstrument from entering the second area.
 56. The distal tip of claim55, wherein, if the second instrument is inserted into the channel whilethe first instrument is disposed in the first area, the secondinstrument is guided into the second area by at least one of the firstinstrument or the instrument directing surface.
 57. The distal tip ofclaim 56, wherein the instrument directing surface is deformable, suchthat, when the second instrument is inserted into the channel, contactbetween the second instrument and the instrument directing surfacecauses the instrument directing surface to change shape and allowpassage of the second instrument into the second area.